Storage battery.



THOMAS A. EDISON,

Of LLEWELLYN PARK, WEST ORANGE, NEW JEBSEY.

STORAGE BATTERY.

Ho Drawing.

To all whom it "m rmmrm Be it known th it I, THOMAS ALVA EDISON, a citizen of the United States, and a resident of Llewellyn Park. West Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Storage Batteries. of which the following is a description.

In prior patents and applications, I have described storage batteries in which an alkaline electrolyte is employed. and in the preferred form of which the positive elements contain alternate layers of hydroxide of nickel and nickel flake and the negativeelements contain electrolytically active iron or oxide of iron. My present invention relates to an improved battery of a similar type, and my principal object is to increase the capacity of such a battery by the provision of an improved negative element.

My invention is based on the discovery that the capacity of the negative element can be materially increased by adding tin or a compound of tin, such as tin monoxid or stannous oxid, to the negative electrode. The finely divided iron preferably employed for said electrode may be prepared by reducing an iron compound, such as ferric oxid. by hydrogen in the manner set forth in my U. S. Patents Nos. 727,117 and 727,118, or in my U. S. Patent No. 1,275,232, dated August 13, 1918, or in any other suitable manner. Before the tin monoxid, which is the compound of tin I prefer to employ. isadded to the finely divided iron, care should be taken to have the same in a very fine state of division. The finely divided tin monoxid should he very thoroughly mixed with the finely divided iron. which may also have a small percentage of mercury mixed or incorporated therewith as set forth in my U. S. Patent No. 727.117, dated Mhy 5, 1903. The

referred amount of tin monoxid employed y me is about 20 per cent. by weight, or in other words. for each 100 grams of active material in the negative element, the amount of tin monoxid used will be preferably about 90 grams. but the proportion may be varied considerably on either side of this qlmltity. As low as 10 per cent. of tin'monoxid shows considerable improvemen in the capacity of the battery. Larger amountsrthan 20 per Specification 01' Letters Patent Application filed August 10, 1314 -pos'.tive elements stores up active material of the negative elements is sartially or completely reduced. During Patented Apr. 8. H9.

Serial No. 856,025.

cent. of tin monoxid still further improve the oi'it'put or capacity of the battery, but the em loyment of tin monoxid very much in excess of 30 per cent. is nnteasible because of the expense of the same. The increase of capacity of a cell of the class in question by reason of the employment of a negative element rontainiug about 20 per cent. of tin monoxid amounts to about 30 per cent. Furthermore. the average voltage at the cell is substantially increased by the employ meat of the tin monoxid. Although I have observed that the above named results are ohtaineiLby my invention, I am not at present able to explain exactly the reason there for. If desired, exceedingly finely divided tin may be. used instead of the tin mermaid, but by reason of the lower cost of the latter, I prefer to use the same. Furthermore, the tin oxid is reduced to metallic tin when the battery is charged.

The electrolytically active material for the negative element after being prepared as do scribed above, is preferably packed in nickel plated steel pockets supported in nickel plated steel plates or frames, such as are shown. in my prior Patent No. 700.131, dated May 13, 1902. The active material tor the positive element. I prefer to load in nickel plated. perforated steel tubes supported in nickel plated steel plates or frames, such as air described in my rior Patents Nos. 896,635 dated August 25,1908; 940.635 dated November 16, 1909: and 976,792 dated November 22, 1910. The elements or electrodes thus formed are assembled in a suitable container such, for example, as a nickel plated steel can. means being provided to insulate the elements of one polarity from those of the opposite polarity. For the electrolyte I prefer to employ a solution of potassium or sodium hydroxid, to which may he added a small percentage of lithium hydroxid, as disclosed in my prior Patent No.-876,44=5. dated January 14, 1908.v During the charging: operation, the active material of the oxygen and the ischarging the active material of the negative elements is oxidized and the oxygen con tents of the active material of the positive elements is decreased. The positive elements may be designated as the depolarizing element.

The expression ferrous material as used in the claims is intended to cover both iron and the oxids thereof: and the expression stannie material as used in the claims is intended to cover both tin and the oxids thereof.

Having now described my invention. what I claim as new therein and desire to protect by Letters Patent of the I uited State is as follows:

1. An active element for storage battery electrodes containing a compound of tin in undissolved condition. substantially as de scribed.

'2. An activeelement for storage battery electrodes containing an oxid of tin, substantially as described.

3. An active element forstorage battery electrodes containing stannous oxid, sub-- stantially as described.

4. An active element for storage battery electrodes containing finely, divided ferrous material and a staunic material. substalr tially as described.

5. An active element for storage battery electrodes containing finely divided ferrous material and an oxid of tin, substantially as described.

6. An active element for storage battery electrodes containing finely divided ferrous material and a small percentage of a staunic material, sulistantially as described.

7. An active element for storage battery electrodes containing finely divided ferrous material and approximately '20 per cent. of an oxid of tin. substantially as described.

8. An active element for storage battery electrodes containing finely divided ferrous material. mercury, and a stannic material, substantially as described.

9: An active element for storage battery electrodes containing finely divided ferrous material. mercury, and an oxid of tin, substantially as described.

10. An active element for storage battery electrodes containing an intimate mixture of finely divided ferrous material, and a finely divided oxid of tin. substantially as de scribed.

11. In a storage battery. a positive element, a negative element containing finely divided ferrous material having a small amount of a stannic material mixed therewitli, and an alkaline electrolyte. substantially as described.

12. In a storage battery, a positive element, a negative element containing finelv divided ferrous material having a mall amount of an (mid, of tin mixed lllli'tWlill, and an alkaline electrolyte. substantially as described.

13. In a storage battery. a ositive element, a negative element containing finely divided ferrous material having a small amount of mercury and a stannic material mixed therewith, and an alkaline electrolyte, substantially as described.

ll. In a storage battery, a positive element containing nickel, a negative element containing a mixture of finely divided iron and a stannie material. and an alkaline elertrr lyte. substantially described. I

15. In a storage battery, a positive element containing nickel. a negative element rontaining a mixture of finely divided ferrous material and a stannic material, and an alkaline electrolyte, substantially as described.

16. In a storage battery, a positive element ontaining nickel, a negative element eon raining a mixture of finely divided ferrous material and an oxid of tin, and an alkaline electrolyte, substantially as described.

1?. In a storage battery, a positive element containing nickel, a negative element containing a mixture of finely divided ferrous material, and a small percentage of mercury and a stannic material, and an al kaline electrolyte, substantially as described.

18. In a storage battery, :1 positive element. a negative element containing a stannic material, and an alkaline electrolyte containing a lithium compound, substantially as described.

19. In a storage battery. a positive. element, :1 negative element containing a mix ture of iron and a stannic material, and an alkaline electrolyte containing lithium hy droxid. substantially as described.

20. In a storage battery, :1 positive element. a negative element containing finely divided ferrous material having a small amount of mercury and a stannie material mixed therewith, and an alkaline electrolyte containing lithium hydroxid, substantially as described.

21. In a. storage battery; :1 positive element containing nickel. a negative element containing a mixture of finely divided iron and a stannie material, and an alkaline. electrolyte containing lithium hydroxid, substantially as described.

In a storage battery, a positive ele ment coi'itaining nickel. a. negati.-'e element containing a HllXlllll'L. ot finely divided ferrous material. and a small percentage of mercury and a slannic material, and an alkaline electrolyte containing lithium hydroxid. substantially as described.

23. An active element for storage battery electrodes containing a compound of tin in undissolvcd condition and mercury. substantially as described.

24. An active element for storage battery electrodes containing an oxid of tin and mercury. substantially as described.

An active element for storage battery electrodes containing stennous oxid and mercury, subsstantially as described.

26. An active element for storage battery electrodes containing a. stannic material and mercury, substantiallyas described.

27. An active element for storage battery electrodes containing mercury and a componnd of tin, substantially as described.

28. In a storage battery; :1 positive element eontainin containing fine 'y divided iron having a nickel, a negative element small amount of mercury and a stannic material mixed therewith and an alkaline electrolyte containing litliium hydroxid, subetantially as described.

This s )ecification signed and witnessed this 6th day of August, 1914.

THOS. A. EDISON.

. Witnesses:

Fnxnmuex Bnomuns, MARY J. LAIDLAW.

Correction in Letters Patent No. 1,299 693.

It is hereby certified that, in Letters Patent No. 1,299,693, granted April 8, 1919, upon tho application of Thomas A. Edison, of Llewellyn Park, West Orango,

New Jersey, for an improvement. in Sburligo Batteries, an error appears in the printed spocificatjon requiring correction as follows: Page 1, line 85, for pal-[ml number 896,635g" road 696,812; and that the said Letters Patent should be read with this correction therein that the same may com'nrm no the record of th case i the Patent; Office.

Signed and sealed this 5th day of August, A. D., 1919.

R. F. WH I'll'JliEA D, Acting; Commissioner of Patents. 

